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Description

The Spotmatic cameras were introduced by Asahi Optical Company in 1964 and marketed through 1976. The camera was one of the first commercially available 35mm SLRs to include through-the-lens metering. The camera name is derived from the use of spot metering on the original design of the camera. The metering system was changed to average metering prior to its release but the change happened too late to change the marketing materials, so the original name continued to be used. A series of different models were made with minor changes and improvements. All Spotmatics use the M42 lens mount. In the United States, Spotmatic cameras were imported and marketed by Honeywell and bear the name "Honeywell Spotmatic". Cameras manufactured for sale outside the US were badged "Asahi Spotmatic".

The Spotmatic SP

The Spotmatic SP was introduced by Asahi Optical Company in 1964, and was one of the first 35mm SLR cameras with through-the-lens light metering. The camera was entirely mechanical apart from the light meter, which was powered by a 1.35 volt PX400 mercury cell. Mercury batteries are now banned but Zinc-Air batteries can be used instead, or it is possible to carry out a minor modification to the meter circuit to allow the use of 1.55 volt 387S silver-oxide batteries. A small switch on the (photographer's) left side of the lens housing was pushed up to stop down the lens and activate the meter; the exposure controls would then be adjusted to center a needle on the right edge of the viewfinder. The body took lenses with an M42 screw thread, providing a large range of available lenses. The system became the workhorse of many professionals of the period. Three variants of the Spotmatic SP are common: 1) Black and chrome body with Asahi Pentax badge on prism housing, Spotmatic badge on front below shutter release and SP badge on top near the rewide knob. 2) All black body with Asahi Pentax badge on prism housing, Spotmatic badge on front below shutter release and SPbadge on top near the rewind knob. 3) Blank and chrome body with Honeywell Pentax badge on prism housing and Spotmatic badge on front below shutter release (but no correspond SPbadge). The Spotmatic SP did not have a hotshoe.

The SL

The Pentax SL is identical to the Spotmatic SP except that it does not include built-in light metering. Like the SP, it came in 3 variants, black and chrome Asahi, black Asahi, black and chrome Honeywell.

The SP500 and SP1000

The SP500 and SP1000 are identical to the Spotmatic SP except there is no self timer and the SP500 shutter speed dial shows a max speed of 1/1000. However, like the SP1000 and SP, the SP500 can actually shoot at 1/1000 by turning the shutter speed dial to an unmarked stop after 1/500. Like the SP, the SP500/SP1000 models came in 3 variants, black and chrome Asahi, black Asahi, black and chrome Honeywell.

The Spotmatic SP II

An updated version of the original Spotmatic SP, launched in 1971. As well as a number of minor improvements to the meter components and film transport, the SP II was fitted with a hot shoe with a switch under the rewind crank for FP and X-flash synchronization and the ASA range was increased to 3200.

The Spotmatic SP F

The Spotmatic SP F, launched in 1973, included several improvements. It was the first version to offer open-aperture metering, but this needed the updated Super-Multi-Coated (S-M-C) Takumar lenses with an aperture-position linkage to the camera. The FP option for the hot shoe synchronisation was dropped and the meter circuit design was revised to take account of the lens aperture setting and to indicate correct exposure when zero current is flowing through the meter, which now allowed for a variation in voltage from the battery. The battery now needed extra capacity and was changed to the now-defunct PX625 mercury cell. The light meter is constantly switched on but there is an automatic cut-off when the light is at EV2 or less, so it is important to keep the lens cap on when the camera is not in use, in order to conserve the battery.

Automatic exposure (aperture priority) and manual mode camera with automatic speeds from 1-1/1000 and manual speeds from 1/60 - 1/1000 seconds. The light meter operates only when the shutter button is pressed and only in auto mode and the meter needle now indicates the auto shutter speed. Open-aperture metering with the S-M-C and SMC Takumar lenses, as for the SP F, is maintained. This camera is powered by one 4SR44 6.2v silver oxide battery and there is a battery check button.

Similar to the ES, but with a self timer, shutter release lock, interior viewfinder blinds and shutter speeds from 8 seconds to 1/1000th second in auto mode. The power supply is now four modern 1.5v alkaline or silver oxide cells.